Microbiology for usmle - quizlet Flashcards
1
Q
N. meningitis
A
Gram- coccus, ferments maltose
2
Q
S. Aureus
A
Gram+ coccus, catalase+, coagulase+
3
Q
S. Pyogenes, S. Agalactiae
A
Gram+ coccus, catalase-, B-hemolysis
4
Q
S. epidermitis, S. saprophyticus
A
Gram+ coccus, catalase+, coagulase-
5
Q
S. Pneumoniae, S. Viridans
A
Gram+ coccus, catalase-, a hemolysis
6
Q
Enterococcus
A
Gram+ coccus, catalase-, y hemolysis
7
Q
S. Pneumoniae
A
Gram+ coccus, catalase-, bile soluble
8
Q
S. Pneumoniae
A
Gram+ coccus, quellung+
9
Q
Listeria
A
Gram+ rod, has endotoxin
10
Q
Clostridium, Bacteroides, Actinomyces
A
Aminoglycosides are ineffective
11
Q
K. Pneumoniae, Salmonella, HiB
A
Gram- rod, quellung+
12
Q
C. diptheriae
A
AB toxin inactivates EF-2
13
Q
ETEC
A
AB toxin (1) activates adenylate cyclase (=> cAMP); AB toxin (2) stimulates guanylate cyclase
14
Q
B. pertussis
A
AB toxin inhibits G(i) protein => increased cAMP
15
Q
C. diptheriae
A
Has an AB toxin that is similar to Pseudomonas exotoxin A in effect
16
Q
B. anthracis
A
Has edema factor (=> cAMP)
17
Q
Streptolysin O
A
Antibody used to dx RF
18
Q
C. botulinum
A
Blocks Ach release
19
Q
C. tetani
A
Blocks GABA and glycine release
20
Q
S. pneumoniae, HiB, N. meningitis
A
Has bacterial competence
21
Q
Listeria
A
Gram + rod, B hemolysis
22
Q
S. Aureus, other catalase producing organisms
A
Affects those with chronic granulomatous disease
23
Q
S. pneumoniae
A
Rusty sputum. Causes sepsis in those with sickle cell anemia, and asplenic patients
24
Q
S. pneumoniae, HiB, N. meningitis
A
Has IgA protease
25
S. pyogenes
Avoids phagocytosis using M protein
26
S. bovis
Causes bacteremia and subacute endocarditis in colon cancer patients
27
Clostridium, B. anthracis
Gram+ rod, spore forming
28
B. anthracis
Has a polypeptide capsule with D-glutamate
29
Actinomyces israelii
Forms sulfur granules in sinus tracts
30
M. leprae
Gram+ bacillus, grows in live cells only.
31
M. leprae (lepromatous form)
Loss of eyebrows, nasal collapse, lumpy earlobe
32
K. pneumoniae, E. coli
Gram- rod, lactose fermenter
33
Pseudomonas
Gram- rod, non-lactose fermenting, oxidase+
34
Shigella, Salmonella, Proteus
Gram- rod, non-lactose fermenting, oxidase-
35
Gram- rods
Resistant to penicillin G and vancomycin, but may be sensitive to derivative (ie ampicillin)
36
H. influenza
Requires NAD and hematin for growth
37
Legionella
Gram- rod, requires silver stain for visualization
38
Legionella: erythromycin
Gram- rod, needs iron and cysteine for growth. Treat with?
39
Pseudomonas: aminoglycoside + extended spectrum PCN
Causes malignant otitis externa in diabetics. Treat with?
40
Pseudomonas
Produces exotoxin A => inactivates EF-2
41
Enterobacteria. All are lactose fermenters and oxidase negative
Have O, K, and H antigens
42
EHEC
Has a Shiga-like toxin. Causes necrosis and inflammation. Does not invade mucosa.
43
EPEC
Gram- rod. Causes diarrhea by flattening villi - no toxin. Associated with clusters.
44
K. Pneumoniae
Causes aspiration pneumoniae, lung abscesses. Infects alcoholics and diabetics. Also causes nosocomial UTI
45
EIEC
Has a Shiga-like toxin, but mucosal invasion is what causes necrosis/inflammation.
46
Typhoid fever, caused by Salmonella typhi
Fever, diarrhea, HA, rose spots on abdomen
47
Salmonella
Non-lactose fermenting gram-rod; has flagella and produces H2S
48
Salmonella
Remains in gallbladder chronically
49
Yersinia enterocolitica
Mimics Crohn's and appendicitis. Major source: pigs
50
H. pylori
Gram- rod, urease+. Risk factor for peptic ulcer, gastric adenocarcinoma, and lymphoma
51
Spirochetes
Visualized with dark field microscopy
52
Borrelia burgorferi: Ixodes tick: doxycycline, ceftriaxone
Causes erythema migrans, bilateral Bell's palsy, AV block, and arthritis. Source? Treat with?
53
Whipple's disease (T. whippeli)
Visualized with PAS stain
54
ETEC (often with campy)
Common cause of Traveler's diarrhea
55
Secondary syphilis
Maculopapular rash on palms and soles, condylomata lata
56
Tertiary syphilis
Chronic granulomas, aortic valve insufficiency, tabes dorsales destruction (ataxia, +Romberg, Charcot joints, stroke w/o HTN)
57
Congenital syphilis
Saber shins, saddle nose, Hutchinson's teeth, deafness, mulberry molars
58
Tertiary syphilis
Argyll Robertson pupil
59
VDRL
Reacts with beef cardiolipin. Can be positive in Viral infxn, drugs, RF, Lupus/leprosy, and syphilis
60
Brucella
associated with unpasteurized dairy products/animals. causes undulent fever.
61
Francisella tularensis
associated with rabbits and deer. requires cysteine for growth. causes ulcers.
62
Pasteurella multocida
cellulitis associated with animal bites (esp cats and dogs)
63
Gardnerella vaginalis: metronidazole
Gram variable rod. Overgrowth of bacteria => fishy smell. Clue cells are visible under microscopy. Treat with?
64
Rickettsiae: TCN
Obligate intracellular organisms that cause a triad of HA, fever, and a rash. +Weil Felix reaction. Treat with?
65
R. rickettsii (rocky mountain spotted fever)
Rash starts on hands and feet, spreads inwards. Transmitted via tick.
66
R. typhi
Rash starts centrally and spreads outwards. Does NOT involve palms or soles
67
Coxiella burnetii
Inhalation of this causes pneumonia ("Q fever"). -Weil Felix reaction
68
Chlamydiae: erythromycin or TCN
Obligate intracellular organism. Has two forms, elementary body and reticulate body. Treat with?
69
Chlamydia psittaci
Atypical pneumoniae, has an avian reservoir
70
Chlamydia trachomatis types L1-3
obligate intracellular organism, +Frei test. causes lymphogranuloma venereum
71
Chlamydia trachomatis types A, B, C
obligate intracellular organism, causes blindness in Africa
72
Chlamydia trachomatis types D-K
obligate intracellular organism, causes reactive arthritis, conjunctivitis, urethritis, PID, ectopic pregnancy
73
M. pneumoniae: TCN/erythrocyclin (PCN resistance d/t no cell wall)
Classic cause of "walking pneumoniae". High amt of IgM. Treat with? Why?
74
Histoplasmosis
pneumonia associated with bat droppings (cave spelunking). location: Mississippi, Ohio river valleys. yeast is smaller than RBC.
75
Blastomycosis
pneumonia, forms granulomatous nodules. location: SE united states. yeast is same as as RBC
76
Coccidioidomycosis
pneumonia and meningitis associated with earthquakes. location: SW united states. yeast is larger than RBC
77
Paracoccidioidomycocis
captain's wheel appearance (budding yeast, larger than RBC)
78
Tinea versicolor
spaghetti and meatball appearance on KOH prep.
79
Malassezia furfur
causes hypopigmented patches on skin
80
dermatocytes (Microsporum, Trichophyton, Epidermophyton): Tinea pedis, cruris, corporis, capitis
causes pruritic lesions with central clearing
81
Aspergillus
monomorphic mold, with hyphae that branch at angles <45 degrees. especially affects immunocompromised and those with chronic granulomatous disease
82
Cryptococcus neoformans
Encapsulated yeast. found in pigeon droppings. "Soap bubble" lesions in brain
83
Mucor and Rhizopus
Dimorphic. Mold has branched hyphae at angles >90 degrees. Afects DKA and leukemia patients. Fungus proliferates in blood vessels => infarct, necrosis.
84
Candida albicans: nystatin (superficial) or amphotericin B (serious/systemic)
Germ tube formation at 37C. Treat with?
85
Pneumocystis jiroveci: TMP-SMX: CD$ <200
Diffuse interstitial pneumonia in immunosuppressed. Treat? When to prophylaxis?
86
Sprothrix schenckii
Dimorphic fungus. Causes ascending lymphangitis (ulcers). Cigar-shaped budding yeast.
87
Giardia lamblia: metronidazole
Foul-smelling, fatty diarrhea. Often encountered in hikers. Treat with?
88
Entamoeba histolytica: metronidazole/iodoquinol
Liver abscess, bloody diarrhea. Histology: flask-shaped ulcer. Treat with?
89
Cryptosporidium: water sanitation
Watery diarrhea; severe in AIDS. Acid-fast cysts. Treat with?
90
Toxoplasma: TMP-SMX
Brain abscess (HIV): ring-enhancing lesions. Treat with?
91
Congenital Toxoplasma
Chorioretinitus, hydrocephalus, intracranial calcifications
92
Naegleria fowleri
Rapidaly fatal meningoencephalitis. From swimming in freshwater lakes
93
Trypanosoma cruzi: reduviid bug (kissing bug)
Dilated cardiomyopathy, megacolon, megaesophagus. Transmitted via?
94
Trypanosoma gambiense/rhodesiense: Tsetse fly
Enlarged lymph nodes, recurring fever, EDS, insomnia, coma. Transmitted via?
95
Leishmania donovani: sandfly
Spiking fevers, hepatosplenomegaly, pancytopenia. Transmitted via?
96
Plasmodium: Anopheles mosquito: Chloroquin (+Primaquine if vivax/ovale)
Malaria: cyclic fever, HA, anemia, splenomegaly. Transmitted via? Treat with?
97
Babesia: Ixodes tick: Quinine/clindamycin
Fever, hemolytic anemia. Blood smear shows maltese cross. Transmitted via? Treat with?
98
Trichomonas vaginalis: metronidazole
Foul smelling, green vaginal discharge. Itching and burning. Treat with?
99
Enterobius vermicularis (pinworm)
Anal pruritis
100
Ascaris (roundworm)
Helminth; Eggs are visible in feces
101
Trichinella spiralis
Larvae encyst in muscle; periborbital edema. Usually found in undercooked pork
102
Strongyloides stercoralis
Larvae in soil penetrate skin => GI, causing vomiting, diarrhea, anemia
103
Ancylostoma duodenale, Necator americanus (hookworm)
Larvae penetrate feet => GI. Sucks blood from intestinal walls => anemia
104
Onchocerca volvulus: blackflies
hyperpigmented skin, river blindness. Transmitted via?
105
Loa loa
Can see worm crawling in conjunctiva
106
Wuchereria bancrofti
causes elephantiasis
107
Toxocara canis
causes granulomas, visceral larva migans. If in retina => blindness
108
Taenia solium
Ingestion => tapeworm (if larvae) or cysts in brain (if eggs)
109
Diphyllobothrium latum
Larvae in raw freshwater fish => B12 deficiency, anemia
110
Echinoccous granulosus
Eggs in dog feces, => anaphylaxis. Must inject ethanol before removal of cysts.
111
Schistosoma
Cercariae => granuloma, fibrosis, inflammation of spleen/liver (portal HTN). Chronic infxn => squamous CC of bladder
112
Clonorchis sinensis
Undercooked fish => cholecystitis => pigmented gallstones. A/w cholangiocarcinoma
113
Paragonimus westermani
Undercooked crab => inflammation, infection of lung => hemoptysis
114
lactobacillus
normal flora of vagina
115
bacteroides
normal flora of colon
116
s. mutans
dental plaques
117
vibro
food poisoning a/w seafood
118
b. cereus
food poisoning a/w reheated rice
119
c. perfringens
food poisoning a/w reheated meat
120
c. botulinum
food poisoning a/w improperly canned food
121
e coli O157:H7
food poisoning a/w undercooked meat
122
salmonella
food poisoning a/w poultry, eggs
123
s. aureus
food poisoning a/w custard, meat, mayo. preformed toxin.
124
S. pneumo, K. pneumo, staph
pneumonia a/w alcoholics or IV drug users
125
psuedomonas
a/w cystic fibrosis
126
listeria
causes meningitis in newborns and elderly
127
s. aureus
MC cause of osteomyelitis
128
pseudomonas
osteomyelitis in diabetics, drug addicts
129
salmonella
osteomyelitis in those with sickle cell
130
pasteurella
osteomyelitis from cat/dog bites/scratches
131
n. gonorrhea/septic arthritis
osteomyelitis in sexually active
132
leukocyte esterase (=> bacterial); nitrite (=> gram-)
diagnostic markers for UTI
133
s. aprophyticus
2nd lead causing of community acquired UTI in sexually active women
134
congenital rubella
PDA, cataracts, deafness, "blueberry muffin" rash
135
congenital CMV
hearing loss, seizures
136
congenital HIV
recurrent infxn, chronic diarrhea
137
congenital HSV
encephalitis, herpetic lesions
138
syphilis
often results in hydrops fetalis
139
Haemophilus decreyi (chancroid)
painful genital ulcer, inguinal adenopathy
140
HSV2
painful penile, vulvar, or cervical ulcers. can cause systemic sx
141
chlamydia, gonorrhea
chandelier sign - MC causes?
142
Trichomonas
vaginitis, strawberry cervix
143
HiB
fever with dysphagia, drooling, difficulty breathing. cherry red epiglottis
144
c. diptheriae
grayish oropharyngeal exudate
145
poliovirus, Hib
meningitis, may lead to myalgia and paralysis
146
bartonella henselae
superficial vascular proliferation
